In general, a pumping-type cosmetic container includes: a container body for storing contents; a piston which is installed at an inner lower portion of the container body and ascends as the contents are discharged; and a pumping means coupled to an upper portion of the container body and discharging the contents stored in the container body by a pumping operation.
The piston installed in the pumping-type cosmetic container like the above is required to allow a sidewall portion thereof in contact with an inner wall of the container body to secure a thickness thicker than a predetermined height in order to prevent a phenomenon in which the piston is upside down due to an internal pressure of the container body during an ascending operation of the piston. However since the piston takes up a lot of inner space of the container body due to the thickness of the piston for a normal operation, there is a problem in that the contents may not be filled by the space taken up by the piston.
Korean utility model registration No. 20-0235847 entitled “Piston of dispenser container” was proposed by the applicant in order to resolve the problem.
The utility model registration is characterized in that a dispenser container includes: a container part 10 for storing contents; a piston 20 which is installed in the container part 10 and ascends as the contents are discharged; and a pumping part 30 coupled to an upper end portion of the container part 10, for discharging the contents to the outside, wherein the piston 20 includes: an inner piston 21 formed in a tubular shape and having an opened upper surface, a bottom 23, and a sidewall 22, the inner piston 21 having locking jaws 24 and 25 each of which is formed on outer circumferential surfaces of an upper end portion and a lower end portion thereof; and an outer piston 26 liftably coupled to the outer circumferential surface of the inner piston 21, the outer piston 26 ascending while an outer circumferential surface thereof is in close contact with an inner wall surface of the container part 10, and wherein the outer piston 26 is positioned at a lower end portion of the inner piston 21 to reduce unused space of the container part 10 while the contents are filled in the container part 10, and the outer piston 26 ascends to the upper end portion of the inner piston 21 to reduce a remaining amount of the contents after the contents are completely discharged.
The utility model registration having the above-described configuration is configured such that the inner piston 21 is formed in the shape of a hollow cylinder having an opened upper portion to fill the contents therein, and thus relatively more contents may be filled in the container having the same volume, and the outer piston 26 ascends to the upper end portion of the inner piston 21 when the contents are completely discharged such that the remaining amount of the contents is reduced.
However, since the utility model registration employs a structure in which the bottom 23 of the inner piston 21 partially contacts the lower portion of the pumping unit 30 during the ascending of the piston 20 due to consumption of the contents, the discharge of the contents by the pumping operation is not smoothly performed within a section in which the outer piston 25 independently ascends, and thus there was a problem in that wasted unused contents still occurred.
Thus, there was a problem in that even though it was possible to fill a relatively larger amount of contents in a container having the same volume, there was little difference in the amount of contents that users could substantially use up.